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TI-2026-15892 Aliases CVE-2026-19534GHSA-rfgv-xxqx-mfg5

undici vulnerable to Denial of Service via unrequested WebSocket subprotocol

Priority LOW 39CWE-248Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
Partial Red Hat: 17 fixed, 11 without a fix

Attack profile from CVSS 3.1 · CNA. Fix status from CNA, GitHub and Red Hat. Impact type from CWE-248.

Summary

undici's WebSocket client crashes the whole Node.js process during the opening handshake when a server responds with a subprotocol that the client never requested. A default WebSocket connection sends no subprotocol, but if the server's 101 response includes a Sec-WebSocket-Protocol header, undici dereferences a null value while checking it against the requested list and throws an uncaught TypeError. Because that code runs inside a microtask with no surrounding error handling, the exception propagates and terminates the process under Node's default behavior, instead of gracefully failing the connection as required by the WebSocket protocol. Any application that opens a WebSocket to an attacker-controlled or compromised server, or over a plaintext connection subject to a machine-in-the-middle, can be crashed remotely without authentication in the default configuration. This affects undici versions from 6.7.0 up to 6.28.1, from 7.0.0 up to 7.29.1, and from 8.0.0 up to 8.10.2. Users should upgrade to undici 6.28.1, 7.29.1, or 8.10.2.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00394 33rd percentileScored 2026-11-07
Fix Partial undici (undici): 6.28.1, 7.29.1, 8.10.2undici (npm): 6.28.1, 7.29.1, 8.10.2Red Hat: 26 advisoriesRed Hat: 17 fixed, 11 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
Yes
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
NodeJSundici6.7.0 to before 6.28.1; 7.0.0 to before 7.29.1; 8.0.0 to before 8.10.26.28.1, 7.29.1, 8.10.2Patch availableCNA
—undici (npm)6.7.0 to before 6.28.16.28.1Patch availableGHSA-rfgv-xxqx-mfg5
—undici (npm)7.0.0 to before 7.29.17.29.1Patch availableGHSA-rfgv-xxqx-mfg5
—undici (npm)8.0.0 to before 8.10.28.10.2Patch availableGHSA-rfgv-xxqx-mfg5
  • undici VendorNodeJS Affected 6.7.0 to before 6.28.1; 7.0.0 to before 7.29.1; 8.0.0 to before 8.10.2 Fixed in 6.28.1, 7.29.1, 8.10.2 Patch available CNA
  • undici (npm) Vendor— Affected 6.7.0 to before 6.28.1 Fixed in 6.28.1 Patch available GHSA-rfgv-xxqx-mfg5
  • undici (npm) Vendor— Affected 7.0.0 to before 7.29.1 Fixed in 7.29.1 Patch available GHSA-rfgv-xxqx-mfg5
  • undici (npm) Vendor— Affected 8.0.0 to before 8.10.2 Fixed in 8.10.2 Patch available GHSA-rfgv-xxqx-mfg5

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:nodejs:undici:*:*:*:*:*:node.js:*:*6.7.0 to before 6.28.1; 7.0.0 to before 7.29.1; 8.0.0 to before 8.10.2VulnerableNodeJS
  • cpe:2.3:a:nodejs:undici:*:*:*:*:*:node.js:*:* Versions 6.7.0 to before 6.28.1; 7.0.0 to before 7.29.1; 8.0.0 to before 8.10.2 Vulnerable ·NodeJS

Remediation

  • Fix · CNA undici (undici) Fixed in 6.28.1, 7.29.1, 8.10.2
  • Fix · GHSA-rfgv-xxqx-mfg5 undici (npm) Fixed in 6.28.1 Advisory →
  • Fix · GHSA-rfgv-xxqx-mfg5 undici (npm) Fixed in 7.29.1 Advisory →
  • Fix · GHSA-rfgv-xxqx-mfg5 undici (npm) Fixed in 8.10.2 Advisory →

Red Hat 26 advisories

  • RHSA-2026:95591 Released 2026-11-05 · Red Hat rating Important
    Cluster Observability Operator - 1.5
    • Cluster Observability Operator 1.5 registry.redhat.io/cluster-observability-operator/alertmanager-rhel9, registry.redhat.io/cluster-observability-operator/cluster-observability-rhel9-operator, registry.redhat.io/cluster-observability-operator/distributed-tracing-console-plugin-pf4-rhel9 +16
  • RHSA-2026:95124 Released 2026-11-04 · Red Hat rating Important
    RHTAS 1.5.1 - Red Hat Trusted Artifact Signer Release
    • Red Hat Trusted Artifact Signer 1.5 registry.redhat.io/rhtas/rhtas-console-rhel9, registry.redhat.io/rhtas/rhtas-console-ui-rhel9
  • RHSA-2026:95081 Released 2026-11-04 · Red Hat rating Important
    Cluster Observability Operator - 1.5
    • Cluster Observability Operator 1.5 registry.redhat.io/cluster-observability-operator/alertmanager-rhel9, registry.redhat.io/cluster-observability-operator/cluster-observability-rhel9-operator, registry.redhat.io/cluster-observability-operator/distributed-tracing-console-plugin-pf4-rhel9 +16
Show 23 more Red Hat advisories
  • RHSA-2026:92650 Released 2026-10-29 · Red Hat rating Important
    Red Hat OpenShift Data Foundation 4.19.26 security, enhancement & bug fix update
    • Red Hat Openshift Data Foundation 4.19 registry.redhat.io/odf4/cephcsi-rhel9, registry.redhat.io/odf4/cephcsi-rhel9-operator, registry.redhat.io/odf4/mcg-core-rhel9 +17
  • RHSA-2026:90321 Released 2026-10-26 · Red Hat rating Critical
    Red Hat OpenShift Dev Spaces 3.31.0 Release.
    • Red Hat OpenShift Dev Spaces 3.31 registry.redhat.io/devspaces/code-rhel9, registry.redhat.io/devspaces/dashboard-rhel9, registry.redhat.io/devspaces/jetbrains-ide-rhel9 +8
  • RHSA-2026:87410 Released 2026-10-21 · Red Hat rating Critical
    RHOAI 2.25.12 - Red Hat OpenShift AI
    • Red Hat OpenShift AI 2.25 registry.redhat.io/rhoai/odh-built-in-detector-rhel9, registry.redhat.io/rhoai/odh-caikit-nlp-rhel9, registry.redhat.io/rhoai/odh-codeflare-operator-rhel9 +47
  • RHSA-2026:86891 Released 2026-10-21 · Red Hat rating Critical
    RHOAI 3.5.2 - Red Hat OpenShift AI
    • Red Hat OpenShift AI 3.5 registry.redhat.io/rhoai/odh-automl-rhel9, registry.redhat.io/rhoai/odh-built-in-detector-rhel9, registry.redhat.io/rhoai/odh-cli-rhel9 +47
  • RHSA-2026:84734 Released 2026-10-19 · Red Hat rating Critical
    RHOAI 3.4.5 - Red Hat OpenShift AI
    • Red Hat OpenShift AI 3.4 registry.redhat.io/rhoai/odh-ai-gateway-payload-processing-rhel9, registry.redhat.io/rhoai/odh-automl-rhel9, registry.redhat.io/rhoai/odh-autorag-rhel9 +47
  • RHSA-2026:84703 Released 2026-10-19 · Red Hat rating Important
    nodejs22 security update
    • Red Hat Enterprise Linux AppStream EUS (v. 10.0) nodejs-1:22.23.2-2.el10_0, nodejs-devel-1:22.23.2-2.el10_0, nodejs-docs-1:22.23.2-2.el10_0 +4
  • RHSA-2026:84589 Released 2026-10-19 · Red Hat rating Important
    nodejs:22 security update
    • Red Hat Enterprise Linux AppStream EUS (v.9.6) nodejs-1:22.23.2-2.module+el9.6.0+25055+19201b10.aarch64::nodejs:22, nodejs-1:22.23.2-2.module+el9.6.0+25055+19201b10.ppc64le::nodejs:22, nodejs-1:22.23.2-2.module+el9.6.0+25055+19201b10.s390x::nodejs:22 +28
  • RHSA-2026:82151 Released 2026-10-13 · Red Hat rating Critical
    Ansible automation portal Red Hat Enterprise Linux Images
    • Red Hat Ansible Automation Platform 2.2 registry.redhat.io/ansible-automation-platform/bootc-automation-portal-rhel9
  • RHSA-2026:76750 Released 2026-10-08 · Red Hat rating Important
    nodejs:22 security update
    • Red Hat Enterprise Linux AppStream (v. 9) nodejs-1:22.23.2-2.module+el9.8.0+24958+80b2ac6e.aarch64::nodejs:22, nodejs-1:22.23.2-2.module+el9.8.0+24958+80b2ac6e.ppc64le::nodejs:22, nodejs-1:22.23.2-2.module+el9.8.0+24958+80b2ac6e.s390x::nodejs:22 +28
  • RHSA-2026:79088 Released 2026-10-08 · Red Hat rating Critical
    Red Hat Developer Hub 1.10.5 release.
    • Red Hat Developer Hub 1.10 registry.redhat.io/rhdh/rhdh-hub-rhel9, registry.redhat.io/rhdh/rhdh-rhel9-operator
  • RHSA-2026:76788 Released 2026-10-06 · Red Hat rating Critical
    Red Hat Developer Hub 1.10.5 Plugin Catalog GA plugins release.
    • Red Hat Developer Hub 1.10 registry.redhat.io/rhdh/red-hat-developer-hub-backstage-plugin-lightspeed, registry.redhat.io/rhdh/red-hat-developer-hub-backstage-plugin-lightspeed-backend, registry.redhat.io/rhdh/red-hat-developer-hub-backstage-plugin-orchestrator +4
  • RHSA-2026:75864 Released 2026-10-05 · Red Hat rating Important
    nodejs22 security update
    • Red Hat Enterprise Linux AppStream (v. 10) nodejs-1:22.23.2-3.el10_2, nodejs-devel-1:22.23.2-3.el10_2, nodejs-docs-1:22.23.2-3.el10_2 +4
  • RHSA-2026:75870 Released 2026-10-05 · Red Hat rating Important
    nodejs:22 security update
    • Red Hat Enterprise Linux AppStream (v. 8) nodejs-1:22.23.2-2.module+el8.10.0+24957+74108fbf.aarch64::nodejs:22, nodejs-1:22.23.2-2.module+el8.10.0+24957+74108fbf.ppc64le::nodejs:22, nodejs-1:22.23.2-2.module+el8.10.0+24957+74108fbf.s390x::nodejs:22 +28
  • RHSA-2026:74609 Released 2026-10-01 · Red Hat rating Important
    Cluster Observability Operator 1.5.3
    • Cluster Observability Operator 1.5 registry.redhat.io/cluster-observability-operator/alertmanager-rhel9, registry.redhat.io/cluster-observability-operator/cluster-observability-rhel9-operator, registry.redhat.io/cluster-observability-operator/distributed-tracing-console-plugin-pf4-rhel9 +13
  • RHSA-2026:74085 Released 2026-09-30 · Red Hat rating Important
    nodejs:24 security, bug fix, and enhancement update
    • Red Hat Enterprise Linux AppStream (v. 8) nodejs-1:24.21.0-1.module+el8.10.0+24927+ed3d907a.aarch64::nodejs:24, nodejs-1:24.21.0-1.module+el8.10.0+24927+ed3d907a.ppc64le::nodejs:24, nodejs-1:24.21.0-1.module+el8.10.0+24927+ed3d907a.s390x::nodejs:24 +25
  • RHSA-2026:73838 Released 2026-09-30 · Red Hat rating Important
    nodejs:24 security, bug fix, and enhancement update
    • Red Hat Enterprise Linux AppStream (v. 9) nodejs-1:24.21.0-1.module+el9.8.0+24924+cd677006.aarch64::nodejs:24, nodejs-1:24.21.0-1.module+el9.8.0+24924+cd677006.ppc64le::nodejs:24, nodejs-1:24.21.0-1.module+el9.8.0+24924+cd677006.s390x::nodejs:24 +25
  • RHSA-2026:73428 Released 2026-09-29 · Red Hat rating Important
    nodejs24 security, bug fix, and enhancement update
    • Red Hat Enterprise Linux AppStream (v. 10) nodejs24-1:24.21.0-1.el10_2, nodejs24-devel-1:24.21.0-1.el10_2, nodejs24-docs-1:24.21.0-1.el10_2 +3
  • RHSA-2026:72722 Released 2026-09-28 · Red Hat rating Important
    Ansible plug-ins for Red Hat Developer Hub Product Release Update
    • Red Hat Ansible Automation Platform 2.2 registry.redhat.io/ansible-automation-platform/automation-portal
  • RHSA-2026:72712 Released 2026-09-28 · Red Hat rating Important
    Ansible plug-ins for Red Hat Developer Hub Product Release Update
    • Red Hat Ansible Automation Platform 2.1 registry.redhat.io/ansible-automation-platform/automation-portal
  • RHSA-2026:71017 Released 2026-09-23 · Red Hat rating Important
    Red Hat Hardened Images RPMs bug fix and enhancement update
    • Red Hat Hardened Images nodejs24-1:24.21.0-1.hum1@aarch64, nodejs24-1:24.21.0-1.hum1@src, nodejs24-1:24.21.0-1.hum1@x86_64 +14
  • RHSA-2026:69248 Released 2026-09-21 · Red Hat rating Important
    Red Hat Developer Hub 1.9.9 release.
    • Red Hat Developer Hub 1.9 registry.redhat.io/rhdh/rhdh-hub-rhel9, registry.redhat.io/rhdh/rhdh-rhel9-operator
  • RHSA-2026:66605 Released 2026-09-11 · Red Hat rating Important
    Red Hat Hardened Images RPMs bug fix and enhancement update
    • Red Hat Hardened Images nodejs26-1:26.8.2-0.1.hum1@aarch64, nodejs26-1:26.8.2-0.1.hum1@src, nodejs26-1:26.8.2-0.1.hum1@x86_64 +14
  • RHSA-2026:66008 Released 2026-09-09 · Red Hat rating Important
    Red Hat Hardened Images RPMs bug fix and enhancement update
    • Red Hat Hardened Images grafana12.4-12.4.10-0.2.hum1@aarch64, grafana12.4-12.4.10-0.2.hum1@src, grafana12.4-12.4.10-0.2.hum1@x86_64

Fixed in the same release

Records fixed by the same vendor advisory or release, as the CNA lists them.

  • Release ·

    undici 6.28.1, 7.29.1, 8.10.2

    3 records Highest priority Priority LOW 3 LOW

    Other records, highest priority first

    • TI-2026-58413 undici vulnerable to Denial of Service via unhandled error in WebSocket permessage-deflate decompressionPriority LOW 27
    • TI-2026-15206 undici vulnerable to downstream response splitting via retry interceptorPriority LOW 17
    Show all 3 records →

Vendor assessments

Red Hat

Red Hat rating: Important. Red Hat's page for this CVE →

ProductStatusPlan or fix
Exploit IntelligenceAffectedNo fix yet
OpenShift PipelinesAffectedNo fix yet
Red Hat Build of Podman DesktopAffectedNo fix yet
Red Hat Enterprise Linux 10AffectedNo fix yet
Red Hat Enterprise Linux 9AffectedNo fix yet
Red Hat Hardened ImagesAffectedNo fix planned: Will not fix
Red Hat OpenShift AI (RHOAI)AffectedNo fix yet
Red Hat OpenShift Container Platform 4AffectedNo fix yet
Red Hat OpenShift Container Platform 5AffectedNo fix yet
Red Hat Openshift Data Foundation 4AffectedNo fix yet
Secrets Management Console for Red Hat OpenShiftAffectedNo fix planned: Will not fix
Cluster Observability Operator 1.5Fixed RHSA-2026:74609, RHSA-2026:95081, RHSA-2026:95591
Red Hat Ansible Automation Platform 2.1Fixed RHSA-2026:72712
Red Hat Ansible Automation Platform 2.2Fixed RHSA-2026:72722, RHSA-2026:82151
Red Hat Developer Hub 1.10Fixed RHSA-2026:76788, RHSA-2026:79088
Red Hat Developer Hub 1.9Fixed RHSA-2026:69248
Red Hat Enterprise Linux AppStream (v. 10)Fixed RHSA-2026:73428, RHSA-2026:75864
Red Hat Enterprise Linux AppStream (v. 8)Fixed RHSA-2026:74085, RHSA-2026:75870
Red Hat Enterprise Linux AppStream (v. 9)Fixed RHSA-2026:73838, RHSA-2026:76750
Red Hat Enterprise Linux AppStream EUS (v. 10.0)Fixed RHSA-2026:84703
Red Hat Enterprise Linux AppStream EUS (v.9.6)Fixed RHSA-2026:84589
Red Hat Hardened ImagesFixed RHSA-2026:66008, RHSA-2026:66605, RHSA-2026:71017
Red Hat OpenShift AI 2.25Fixed RHSA-2026:87410
Red Hat OpenShift AI 3.4Fixed RHSA-2026:84734
Red Hat OpenShift AI 3.5Fixed RHSA-2026:86891
Red Hat OpenShift Dev Spaces 3.31Fixed RHSA-2026:90321
Red Hat Openshift Data Foundation 4.19Fixed RHSA-2026:92650
Red Hat Trusted Artifact Signer 1.5Fixed RHSA-2026:95124
Not affected: 15 products
  • Cluster Observability Operator 1.5
  • Cryostat 4
  • Red Hat AMQ Broker 7
  • Red Hat Ansible Automation Platform 2
  • Red Hat Developer Hub 1.10
  • Red Hat Developer Hub 1.9
  • Red Hat Enterprise Linux 10
  • Red Hat Hardened Images
  • Red Hat OpenShift AI 2.25
  • Red Hat OpenShift AI 3.4
  • Red Hat OpenShift AI 3.5
  • Red Hat OpenShift Container Platform 4
  • Red Hat OpenShift Dev Spaces 3.31
  • Red Hat Openshift Data Foundation 4.19
  • Red Hat Trusted Artifact Signer 1.5

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-19534
  2. 2026-10-03 Alias added: GHSA-rfgv-xxqx-mfg5
  3. 2026-10-06 Fix available: RHSA-2026:75870 · Red Hat
  4. 2026-10-06 Fix available: RHSA-2026:75864 · Red Hat
  5. 2026-10-06 Affected versions changed · Red Hat
  6. 2026-10-07 Fix available: RHSA-2026:76788 · Red Hat
  7. 2026-10-07 Fix available: Red Hat Developer Hub 1.10 · Red Hat
  8. 2026-10-08 Affected versions changed · Red Hat
  9. 2026-10-09 Fix available: RHSA-2026:76750 · Red Hat
  10. 2026-10-09 Fix available: RHSA-2026:79088 · Red Hat
  11. 2026-10-09 Affected versions changed · Red Hat
  12. 2026-10-13 Affected versions changed · Red Hat
  13. 2026-10-13 Fix available: RHSA-2026:82151 · Red Hat
  14. 2026-10-16 Affected versions changed · Red Hat
  15. 2026-10-18 Affected versions changed · Red Hat
  16. 2026-10-20 Fix available: RHSA-2026:84703 · Red Hat
  17. 2026-10-20 Fix available: RHSA-2026:84589 · Red Hat
  18. 2026-10-20 Fix available: RHSA-2026:84734 · Red Hat
  19. 2026-10-20 Fix available: Red Hat Enterprise Linux AppStream EUS (v. 10.0), Red Hat Enterprise Linux AppStream EUS (v.9.6), Red Hat OpenShift AI 3.4 · Red Hat
  20. 2026-10-22 Fix available: RHSA-2026:86891 · Red Hat
  21. 2026-10-22 Fix available: RHSA-2026:87410 · Red Hat
  22. 2026-10-23 Fix available: Red Hat OpenShift AI 2.25, Red Hat OpenShift AI 3.5 · Red Hat
  23. 2026-10-29 Fix available: Red Hat OpenShift Dev Spaces 3.31 · Red Hat
  24. 2026-10-30 Fix available: RHSA-2026:90321 · Red Hat
  25. 2026-10-30 Affected versions changed · Red Hat
  26. 2026-10-30 Fix available: Red Hat Openshift Data Foundation 4.19 · Red Hat
  27. 2026-10-31 Fix available: RHSA-2026:92650 · Red Hat
  28. 2026-11-04 Affected versions changed · Red Hat
  29. 2026-11-04 Fix available: RHSA-2026:95081 · Red Hat
  30. 2026-11-04 Fix available: RHSA-2026:95124 · Red Hat
  31. 2026-11-04 Fix available: Cluster Observability Operator 1.5, Red Hat Trusted Artifact Signer 1.5 · Red Hat
  32. 2026-11-06 Affected versions changed · Red Hat
  33. 2026-11-06 Fix available: RHSA-2026:95591 · Red Hat

References

Advisory 3

Other 7

  • TI-2026-01215 undici is vulnerable to Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling') CVSS 3.1CRITICAL 9.8
  • TI-2022-16376 `undici.request` vulnerable to SSRF using absolute URL on `pathname` CVSS 3.1CRITICAL 9.8
  • TI-2023-09734 CRLF Injection in Nodejs ‘undici’ via host CVSS 3.1MEDIUM 6.5
  • TI-2022-13193 CRLF injection in request headers CVSS 3.1MEDIUM 6.5
  • TI-2022-16375 CRLF Injection in Nodejs ‘undici’ via Content-Type CVSS 3.1MEDIUM 5.3
  • TI-2022-13194 Uncleared cookies on cross-host/cross-origin redirect in undici CVSS 3.1MEDIUM 6.5
See all 51 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences